The invention relates, generally, to the outside distribution plants of telecommunications networks and, more particularly, to a method and apparatus for crossconnecting transmission members in the outside distribution plant to create greater flexibility and efficiency in the providing of combined narrowband and broadband signals to the customer.
It will be appreciated that the typical telecommunications network consists of a plurality of switching systems connected to one another to allow the transmission of signals therebetween. Certain of the switching systems, usually referred to as central office switches, are connected to customer premise equipment (customer line) such as telephones, fax machines, multimedia equipment, personal computers and the like by an outside distribution plant such that the customer lines can communicate with one another via the network.
The outside distribution plant typically consists of optical links connecting the switching systems to remote terminals such as digital loop carriers. One such digital loop carrier is the SLC.RTM. digital loop carrier manufactured and sold by Lucent Technologies Inc. Digital loop carriers function to provide less expensive loops than copper loops by converting switch interfaces to fiber and back to copper at the remote terminal and consist of an optical remote terminal that interfaces with the optical links from the switching systems. The optical remote terminal connects the optical links to a plurality of line cards where each line card hosts transmission members such as twisted pair distribution lines. It is further known in the art to provide broadband remote terminals for delivering broadband signals and narrowband remote terminals for delivering narrowband signals.
It will be appreciated that different types of line cards support these different types of service. For example, the most common line card supports narrowband service such as POTS service. Other narrowband line cards support coin service, ISDN service, and special service such as data port, DC alarm, radio broadcast and other special services. Broadband line cards support broadband service such as asynchronous transfer mode (ATM) carried on one of a family of digital subscriber lines (DSL), switched digital video (SDV) or the like. Each line card includes one or more line circuits to which the distribution lines are connected and that control the processing of signals over those lines. Common circuitry is also provided on each line card to control functions common to all of the lines hosted by that line card. It will be understood that common control elements are provided to drive all of the line cards in a remote terminal.
In one distribution plant configuration, combined broadband and narrowband signals are delivered over a single customer line by combining a broadband signal from a broadband line card with a narrowband signal from a narrowband line card using a diplex filter. While the combined narrowband and broadband signal is advantageous, the lines connecting the broadband line cards and the narrowband line cards are hardwired such that the network operator must predict when configuring the network, the demand for the combined signal including the number and identity of customer lines that are to receive the combined signal. Because it is difficult to predict customer demand for such a service, it is virtually inevitable that certain network resources either will remain unused, if fewer customers than predicted request the service, or that insufficient resources will be allocated and some customers will be unable to obtain the service, if a greater number of customers than predicted request the service. Such a situation obviously results in the inefficient use of network resources.
Thus, an improved method and apparatus for more efficiently distributing broadband and narrowband line card functionality over the outside distribution plant is desired.